Modular closed cycle turbine system

ABSTRACT

The modular closed cycle turbine system is advocated as a compact, unitized power system, in which the major components are connected in an optimum working relationship. The helical expansion condenser (HEC), is hollow so that the power fan, turbine expander, auxiliary cooling turbine, and gear reduction unit are nested within the cylindrical cavity. The flat vapor generator ring (VGR) is mounted directly below the HEC and completely insulated from it, so that a minimum of thermal losses are incurred. The VGR is also hollow so that the turbine expander and other components occupy the open cavity, for compactness and unification. All other components of the system are placed in normal operating relationship to each other within the two formed cavities.

[4 1 Jan. 21, 1975 MODULAR CLOSED CYCLE TURBINE SYSTEM [76] Inventor: Donald A. Kelly, 5806 69th PL,

Maspeth, NY. 11378 [22] Filed: Feb. 8, 1972 [21] Appl. No.: 224,416

[52] US. Cl. 60/669 [51] Int. Cl. F01k 11/00 [58] Field of Search 60/92, 34, 36, 73, 108, 60/690; 122/250 R; 165/125 [56] References Cited UNITED STATES PATENTS 928,261 7 1909 Knapp 122/250 R 1,783,126 11/1930 Lysholm 60/73 2,079,923 5/1937 Pavlecka 60/108 2,260,594 10/1941 Y0ung.... 165/125 2,709,895 6/1955 Mount 60/108 R 3,293,851 12/1966 Hulbert 60/108 R Primary ExaminerMartin P. Schwadron Assistant Examiner-H. Burks, Sr.

[57] ABSTRACT The modular closed cycle turbine system is advocated as a compact, unitized power system, in which the major components are connected in an optimum working relationship.

The helical expansion condenser (HEC), is hollow so that the power fan, turbine expander, auxiliary cooling turbine, and gear reduction unit are nested within the cylindrical cavity.

The flat vapor generator ring (VGR) is mounted directly below the HEC and completely insulated from it, so that a minimum of thermal losses are incurred. The VGR is also hollow so that the turbine expander and other components occupy the open cavity, for compactness and unification.

All other components of the system are placed in normal operating relationship to each other within the two formed cavities.

6 Claims, 5 Drawing Figures SHEET 10F 2 FIG.

FIG.Z

PATENTEU SHEET 2 0F 2 F'IG.5

MODULAR CLOSED CYCLE TURBINE SYSTEM BACKGROUND OF THE INVENTION The present invention has been evolved from a consideration of the various deficiencies of previous design efforts, and the necessity of attaining a simplified Rankine cycle modular power package with stationary heat transfer components.

The numerous advantages of the closed Rankine cycle for vehicular propulsion, make the development of improved heating and condensation components well worth the effort, along with a continuing thorough investigation of all possible techniques, including dynamic devices, electronics, materials and component relationships.

The recent advent of the combined rotating boiler and condenser appears to be a major step forward in closed Rankine cycle technology. This promising dynamic arrangement provides for natural vapor/condensate flow by centrifugal force and in considerably shortening the full vapor/condensate flow loop, so that extensive heat exchange tubing runs and complexity is eliminated.

It becomes clear that the shortening of the total vapor/condensate flow loop, while maintaining a maximum delta temperature between the extreme points of the cycle for a given working medium, is the major problem to be resolved in a practical and economical way.

The key to achieving a practical solution appears to be in systematically utilizing economical dynamic, or active components along with electronic devices and controls, in a compact closed loop arrangement. These means must be evolved if the closed Rankine cycle is to become the future power source for many low air pollution applications.

SUMMARY OF THE INVENTION This invention relates to a modular or unitized closed cycle turbine system in which the various evolved components are thoughtfully configured and arranged in relationship to all other units, within a closed loop systern.

The turbine expander utilized for the system is an impulse vapor jet type with multiple input nozzles, some of which are at a maximum radius on the nozzle plate, and others at a lesser radius, for a wider range of speed torque characteristics.

The single stage impulse type turbine (expander), is more fully described in another disclosure and is proposed as a built up sheet metal and plate component, rather than a fully machined, forged or cast expander. The formed and fabricated type of turbine expander would considerably lower the cost of such a desirable unit, which at the present time has been shown to be prohibitably high.

The previously described auxiliary cooling turbine (ACT) would be applied in the system as the power source for the: l) The large airflow cooling fan required, 2) The rotary pump and 3) The electrical alternator.

The auxiliary cooling turbine must produce an estimated horsepower equivalent to about 15 percent of the main turbine expander, due to the large power demands of the aforementioned auxiliary components.

Since the ACT revolves at a high speed like the tur' bine expander, suitable speed reduction means must he made for some of the auxiliaries. The auxiliary cooling turbine (ACT) must be secured to and placed directly above the turbine expander, within the helical expansion condenser cavity, so that it is exposed to the fan induced airflow. Multiple large cooling fins will be uniformly secured tothe ACT for increased cooling. Multiple short heat pipes will also be required for the ACT,

either on the exposed external surfaces or within the impeller housing.

The hot vapor transfer duct running from the ACT to the top intake port of the helical expansion condenser (HEC), must also be effectively finned to remove heat from the duct. This transfer duct must widely loop around, at the direct rear of the HEC, so that it is fully exposed to the continuing airflow leaving the rear of the HEC. Both the ACT and transfer duct act as precooling elements within the system, prior to the hot vapor flow into the HEC.

The large air cooling fan may be directly secured to the front shaft of the ACT, or suitably driven by remote means. The large fiberglas fan moves a high volume of air over the l-IEC duct surfaces, both forward and aft of the fan for maximum exposure of the heat transfer surfaces.

The helical expansion condenser (HEC) was evolved by the necessity of building an effective condensation means which minimizes vapor flow resistance, and is essentially a continuouous coiled duct, formed in a large diameter uniform helix.

The helical expansion condenser (HEC) cools the hot vapor by extended heat transfer surface area and the uniform expansion of the working medium. The elliptical duct surfaces are microfinned for effective heat rejection and multiple heat pipes are the key heat sinking device utilized throughout the continuous duct length. The heat pipes are generally effective heat transfer devices which are economical and easily placed within the continuous coiled duct.

Multiple thermoelectric cooling cells may also be directly mounted on the continuous duct, as an optional item.

The condensate from the lower portion of the HEC is collected in the exit chamber and is gravity fed into the rotary pump which forces the working fluid into the heating coils of the vapor generator ring (VGR).

Since the working fluid enters the VRG at the top of the housing and the vaporized medium exits at the bottom, less pumping power is required for the rotary pump, than in previous stationary component arrangements.

The rotary pump is mounted horizontally on the VGR housing so that both the inlet and exit ports are convenient to the HEC and VGR connections, respectively. The rotary pump may be driven by a flexible shaft from the auxiliary cooling turbine (ACT), rcar shaft, or alternately by an electric motor.

The vaporized medium leaving the bottom of the VGD, is ducted to the multiple input nozzles of the turbine expander. Throttling means is located within the duct to control and meter the vapor flow into all of the nozzles. During vehicle startup, all maximum radiuslangular nozzles are operational, and as the vehicle picks up speed the shorter radius/smaller angle nozzles are utilized for more effective speed/torque characterlstics.

A gear reduction unit must be connected to the rear output shaft of the turbine expander, to reduce the normal high speeds of the turbine to a useable level. The gear reduction unit must be specially designed to fit into the remaining lower cavity space, with its rear output shaft located between the HEC and the VGR.

The output shaft from the gear reduction unit must extend beyond the VGR, and be suitably housed. Because of the need for workable component placement, it may be necessary to add a geared step unit to the automatic transmission, so that it is in a proper height position for connection to the drive shaft of a standard vehicle.

A protective steel plate must be located under the VGR, for protection of this component and the multiple burner tubes, from road debris damage. Since the multiple burner tubes are placed low at the front of the vehicle, the fuel may be gravity fed from the rear fuel tank(s). A fuel pump may be an optional item for the system.

The alternator can be directly driven by the rear shaft of the ACT, or may be connected by a belt drive arrangement. It may also be feasible to drive the alternator from the gear reduction unit, if there is insufficient space around the ACT.

The short-run sustaining motor (SSM) will be located within the VGR cavity with direct coupling, axially, to the turbine expander, through a conventional engage/- disengage clutch. The SSM provides instantaneous starting and a short time running period for the vehicle, until the turbine expander is operating at approximately its mid-power range.

Several twelve volt batteries will be required for the system because of the additional ampere-hours rating required by the SSM, and possibly the thermocells, discharge rate. The alternator must be of sufficient capacity to recharge the batteries at a conventional rate.

Due to the expected excessive height of the total turbine system, the hood height of the vehicle will be increased slightly, since normal road clearance must be maintained. The extra height of the modular turbine package may lead to the placement of the power system at the rear of the vehicle. Some latitude exists in the total height of the system, in that the diameter of the HEC may be increased, so that the height may be reduced.

At the heart of the modular closed cycle turbine system concept is the fact that in placing stationary Rankine cycle components, the condensation means wants to be placed above the heating means, so that the force of gravity is applied on the condensed working medium to minimize return pumping requirements. The gravity flow arrangement 'also supports minimizing working medium flow resistance within the closed loop, due to the considerable total weight of the working medium.

As an integral part of the modular turbine system, there is considerable advantage to the placement of the large cooling fan within the HEC central cavity, with the ACT and its wide loop transfer duct exposed to the high volume air flow, so that precooling of the vapor is provided.

The hot vapor flow from the turbine expander is immediately exposed to the cooling air flow over the ACT and transfer duct, and exposed heat pipes, prior to entrance into the HEC.

The VGR must be shielded from the incoming airflow, so that it is not exposed to any cooling effect. It

is possible that auxiliary heating means may be added to the VGR, if necessary, which can be located on either side of the VGR, and at the rear of the unit.

Effective thermal shielding will be required for both the VGR and HEC. The insulation means these two units must be fully adequate to thermally isolate the units.

Insulation must also be provided at the top of the HEC to prevent radiation heating of this unit.

All of the components of the modular closed cycle turbine system will be assembled and installed as one unit, for connection to the automatic transmission of the vehicle.

The HEC features a device to hasten condensation within the cooling vapor flow path, known as the condensation accelerator grid (CAG). The condensation accelerator grid is intended to speed up condensation, so that full fluidization occurs early within the lower tiers of the continuous duct coil.

It is advantageous to accomplish condensation as quickly as possible within the duct coil so that the total number of coils may be reduced, or to promote the gravity feeding of the fluid toward the vapor generator ring (VGR), beneath the HEC, under an increased pressure head.

The CAG consists of multiple thin metallic sheets, uniformly placed both internally and externally within the duct cross-section. The thin grid sheets are thermally insulated and sealed on the continuous coiled duct. Multiple cooling thermocells are directly mounted to the external surfaces on the grid sheets so that the grid sheets produce a cooling effect within the duct.

The cooling thermocells must be placed at the side portions of the duct coil, outside of the forced cooling air flow from the power fan, to achieve a balanced cooling effect thruout the vapor cooling path.

The various objectives of the invention have been described in the background and summary of the system. It should be understood that variations may be made in the various components of the system, without departing from the spirit and scope of the invention.

REFERRING TO THE DRAWINGS FIG. 1 is a plan view of the modular closed cycle turbine system.

FIG. 2 is a side elevation view of the modular closed cycle turbine system.

FIG. 3 is a front elevation view of the modular closed cycle turbine system.

FIG. 4 is a cross-section of the HEC duct, showing the condensation accelerator grid.

FIG. 5 is a longitudinal cross-section of the HEC duct, showing the condensation accelerator grid.

REFERRING TO THE DRAWINGS IN DETAIL The turbine or engine expander l, is connected to the gear reduction unit 2, and the automatic transmission 3.

The short-run sustaining motor 4, is connected to the expander output shaft at the front section, through an overrunning clutch, or conventional starter clutch 5.

An auxiliary expander turbine 6,-is directly mounted to the top of the turbine or engine expander l, with sealed duct connection means between the expander l, exhaust vapor outlet and the inlet port of the auxiliary expander turbine 6. The auxiliary expander turbine 6, is fitted with large cooling fins 6a.

Multiple heat pipes 612, will be mounted on, or within the auxiliary expander turbine 6, housing. A large fiberglass fan 7, is mounted on the front shaft of the auxiliary expander turbine 6, and a flexible drive 8, is connected to the rear shaft of the auxiliary expander turbine 6, which drives the rotary pump 9.

The rotary pump 9, is mounted on the inner diameter of the vapor generator ring, VGR, 10, so that the working condensate is pumped directly into the heating coils of the vapor generator ring 10. The vapor generator ring 10, encircles the turbine or engine expander 1, so that the system is compact.

The vapor exit duct 11, exiting from vapor generator ring 10, is connected to the input nozzles of the turbine or engine expander 1.

The helical expansion condenser 12, encircles a portion of the turbine or engine expander 1, the auxiliary expander turbine 6, and the fan 7, for a compact total power system. The vapor transfer duct 13, connects the vapor outlet from the auxiliary expander turbine 6, to the entrance plenum of the helical expansion condenser 12. The vapor transfer duct 13, is formed in a large vertical loop directly aft of the HEC 12, with large multiple cooling fins 13a, horizontally secured to the transfer duct 13. The vapor transfer duct 13, arranged in this manner functions as a vapor precooling element within the system.

The condensate outlet duct 14, at the bottom of the helical expansion condenser 12, returns the fluid working medium to the rotary pump 9, for transfer to the vapor generator ring 10, under gravity and pumping pressure. The outlet duct 14, is provided with regeneration conductors 14a, connected to the VGR 10, for preheating of the returned working fluid.

An automotive type alternator 15, is mounted to the gear reduction unit 2, and driven by a take-off drive from the gear reduction unit 2.

A thermal shield 16, is located between the helical expansion condenser 12, and the vapor generator ring 10, to thermally isolate these two components.

The condensation accelerator grid 7, consists of multiple horizontal and vertical thin fins 18, uniformly interposed within the duct coil of the HEC 12.

The thin fins 18, are staggered along the radius of the duct coil so that they do not interfere with each grouping, and may be readily assembled. The thin fins 18, are insulated from the duct coil, by the insulators 19.

Multiple cooling thermocells 20, are secured directly to the thin fins 18, external to the duct coil.

Electric battery means 21, supplies the electrical energy for the cooling thermocells 20, during their operation.

What is claimed is:

l. A modular closed cycle turbine system comprising a vapor turbine expander driven by expanding vapor force, a circular ring-like vapor generator centrally disposed around said vapor turbine expander, a helical expansion condenser centrally disposed around a portion of said vapor turbine expander above said circular ringlike vapor generator, a short time running electric motor intermittently coupled to said vapor turbine expander,

an auxiliary expansion turbine mounted to the top portion of said vapor turbine expander, duct connection means disposed between said auxiliary expansion turbine and said vapor turbine expander,

a large air moving fan secured to said auxiliary expansion turbine which is centrally disposed within said helical expansion condenser,

a rotary pump mounted to said circular ring-like vapor generator driven by flexible drive means from said auxiliary expansion turbine, regeneration means disposed between said circular ring-like vapor generator and said rotary pump,

sealed duct connection means disposed between said helical expansion condenser and said rotary pump,

vapor transfer duct means rearwardly disposed between the exit port of said auxiliary expansion turbine and the entrance of said helical expansion condenser, multiple horizontal fins uniformly disposed on said vapor transfer duct,

duct connection means disposed between said rotary pump and said circular ring-like vapor generator,

an alternator coupled to said modular closed cycle turbine system,

thermal isolation means disposed between said helical expansion condenser and said circular ring-like vapor generator.

2. The modular closed cycle turbine system of claim 1, wherein said helical expansion condenser contains condensation accelerator grids comprised of multiple horizontal and vertical thin fins uniformly disposed within the duct coil of said helical expansion condenser,

multiple cooling thermocells uniformly secured to the external surfaces of the multiple horizontal and vertical thin fins, insulation means disposed between the multiple horizontal and vertical thin fins,

electric storage battery means for said multiple cooling thermocells.

3. The modular closed cycle turbine system of claim 1, wherein said circular ring-like vapor generator contains a vapor exit duct which is connected to multiple nozzles of said vapor turbine expander,

insulation and regeneration means disposed over the vapor exit duct.

4. The modular closed cycle turbine system of claim 1, including a gear reduction unit connected to the rear of said vapor turbine expander,

an automatic transmission connected to the output shaft of the gear reduction unit. 7

5. The modular closed cycle turbine system of claim 1, wherein said auxiliary expansion turbine contains multiple large horizontal cooling fins uniformly disposed on all surfaces,

multiple heat pipes secured to the exposed surfaces of said auxiliary expansion turbine.

6. The modular closed cycle turbine system of claim 1, wherein said regeneration means disposed between said circular ring-like vapor generator and said rotary pump receives heat flow from said duct connection means and exposed surfaces of said circular ring-like vapor generator. 

1. A modular closed cycle turbine system comprising a vapor turbine expander driven by expanding vapor force, a circular ring-like vapor generator centrally disposed around said vapor turbine expander, a helical expansion condenser centrally disposed around a portion of said vapor turbine expander above said circular ring-like vapor generator, a short time running electric motor intermittently coupled to said vapor turbine expander, an auxiliary expansion turbine mounted to the top portion of said vapor turbine expander, duct connection means disposed between said auxiliary expansion turbine and said vapor turbine expander, a large air moving fan secured to said auxiliary expansion turbine which is centrally disposed within said helical expansion condenser, a rotary pump mounted to said circular ring-like vapor generator driven by flexible drive means from said auxiliary expansion turbine, regeneration means disposed between said circular ring-like vapor generator and said rotary pump, sealed duct connection means disposed between said helical expansion condenser and said rotary pump, vapor transfer duct means rearwardly disposed between the exit port of said auxiliary expansion turbine and the entrance of said helical expansion condenser, multiple horizontal fins uniformly disposed on said vapor transfer duct, duct connection means disposed between said rotary pump and said circular ring-like vapor generator, an alternator coupled to said modular closed cycle turbine system, thermal isolation means disposed between said helical expansion condenser and said circular ring-like vapor generator.
 2. The modular closed cycle turbine system of claim 1, wherein said helical expansion condenser contains condensation accelerator grids comprised of multiple horizontal and vertical thin fins uniformly disposed within the duct coil of said helical expansion condenser, multiple cooling thermocells uniformly secured to the external surfaces of the multiple horizontal and vertical thin fins, insulation means disposed between the multiple horizontal and vertical thin fins, electric storage battery means for said multiple cooling thermocells.
 3. The modular closed cycle turbine system of claim 1, wherein said circular ring-like vapor generator contains a vapor exit duct which is connected to multiple nozzles of said vapor turbine expander, insulation and regeneration means disposed over the vapor exit duct.
 4. The modular closed cycle turbine system of claim 1, including a gear reduction unit connected to the rear of said vapor turbine expander, an automatic transmission connected to the output shaft of the gear reduction unit.
 5. The modular closed cycle turbine system of claim 1, wherein said auxiliary expansion turbine contains multiple large horizontal cooling fins uniformly disposed on all surfaces, multiple heat pipes secured to the exposed surfaces of said auxiliary expansion turbine.
 6. The modular closed cycle turbine system of claim 1, wherein said regeneration means disposed between said circular ring-like vapor generator and said rotary pump receives heat flow from said duct connEction means and exposed surfaces of said circular ring-like vapor generator. 